1

DESIGN AND DEVELOPMENT OF A DIFFERENTIAL USING

TWO ONE-WAY CLUTCHES (FREEWHEEL) in SAE BAJA

VEHICLE

SUBMITTED BY:

DIVYANSH SINGH (2k12/ME/070)

SAURABH DUBEY (2K12/ME/157)

SUSHANT SAHASRABUDDHE (2K12/ME/176)

VINEET MATHEW (2K12/ME/190)

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May, 2015

CERTIFICATE

This is to certify that the project titled DESIGN AND DEVELOPMENT

OF A DIFFERENTIAL USING TWO ONE-WAY CLUTCHES in SAE

BAJA VEHICLE submitted by Divyansh Singh (2K12/ME/070), Sushant

Sahasrabuddhe (2K12/ME/176), Vineet Mathew (2K12/ME/190) and

Saurabh Dubey (2K12/ME/157) in partial fulfilment for the award of the

degree of Bachelor of Technology in Mechanical Engineering from Delhi

Technological University (Formerly Delhi College of Engineering) for

their Minor II project in the 6th semester is an authentic work carried out

by them under my supervision and guidance

Prof. Vijay Gautam

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DECLARATION

We, Divyansh Singh, Saurabh Dubey, Vineet Mathew and Sushant

Sahasrabuddhe belonging to Bachelor of Technology, Mechanical

Engineering of Delhi Technological University (Formerly Delhi College of

Engineering) hereby declare that the work presented in the project entitled

DESIGN AND DEVELOPMENT OF A DIFFERENTIAL USING

TWO ONE-WAY CLUTCHES in SAE BAJA VEHICLE in fulfilment

of the minor project of the 6th semester is an authentic record of our work

carried out during the period from January 2015 to May 2015 under the

supervision of Prof. Vijay Gautam.

( ) ( ) ( ) ( )

Signature of Students

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LIST OF SYMBOLS AND ABBREVIATIONS

i Torque required ideally

a Actual torque

e Engine torque

Gradient

Efficiency

- Coefficient of Friction

coefficient of rotational inertia

Density a Acceleration dg Diameter of pinion dp Diameter of gear F - Force

m mass with driver

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CONTENTS

LIST OF SYMBOLS AND ABBREVIATION ............................................................................... 4

INTRODUCTION ............................................................................................................................ 8

Types of Differentials ................................................................................................................. 9

DESIGN METHODOLOGY.........................................................................................................11 Calculation of Torque11 FORCES BALANCED ON THE VEHICLE............................................................................................................... 12 CASE I: .................................................................................................................................................................. 12 CASE II: ................................................................................................................................................................. 13 CONSTRUCTION AND LAYOUT ................................................................................................ 14

LITERATURE REVIEW................................................................................................................. 15 PAPER NO. 1 ........................................................................................................................................................ 15 PAPER NO. 2 ........................................................................................................................................................ 17 PAPER NO. 3 ........................................................................................................................................................ 19 PAPER NO. 4....20 PAPER NO. 5....20 PAPER NO. 6....21 Inference from the Research Papers Studied..22

CONCLUSION 23

RESEARCH GAPS AND SCOPE FOR FUTURE WORK ........................................................... 24

WORK TO BE DONE IN FUTURE25

REFERENCES..26

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ABSTRACT

The objective of this project is to create an automotive differential using

two one-way freewheel clutches. A freewheel differential has advantages

of both open and locked type differentials. With the help of ratchet like

action of a simple freewheel, the wheels connected to a freewheel move in

one direction. A freewheel disengages and engages the driven wheels

according to the wheels relative velocity with respect to the engine. This

action of a freewheel can be used to the wheel rotating faster while the

vehicle is making a turn, thus no slip occurs.

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INTRODUCTION

A Differential has the following aims:

To aim the engine power at the wheels

To act as the final gear reduction in the vehicle, slowing the

rotational speed of the transmission one final time before it hits the

wheels

To transmit the power to the wheels while allowing them to rotate at

different speeds (This is the one that earned the differential its name.)

Car wheels spin at different speeds, especially when turning. Each wheel

travels a different distance through the turn, and that the inside wheels

travel a shorter distance than the outside wheels. Since speed is equal to the

distance travelled divided by the time it takes to go that distance, the wheels

that travel a shorter distance travel at a lower speed. Also note that the front

wheels travel a different distance than the rear wheels.

For the non-driven wheels on your car -- the front wheels on a rear-wheel

drive car, the back wheels on a front-wheel drive car -- this is not an issue.

There is no connection between them, so they spin independently. But the

driven wheels are linked together so that a single engine and transmission

can turn both wheels. If your car did not have a differential, the wheels

would have to be locked together, forced to spin at the same speed. This

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would make turning difficult and hard on your car: For the car to be able to

turn, one tire would have to slip. With modern tires and concrete roads, a

great deal of force is required to make a tire slip. That force would have to

be transmitted through the axle from one wheel to another, putting a heavy

strain on the axle components.

TYPES OF DIFFERENTIALS

Open Differential: Equal Torque

Locked Differential: Equal Speed

In mechanical or automotive engineering, a freewheel or overrunning

clutch is a device in a transmission that disengages the driveshaft from the

driven shaft when the driven shaft rotates faster than the driveshaft. An

overdrive is sometimes mistakenly called a freewheel, but is otherwise

unrelated.

The condition of a driven shaft spinning faster than its driveshaft exists in

most bicycles when the rider holds his or her feet still, no longer pushing

the pedals. In a fixed-gear bicycle, without a freewheel, the rear wheel

would drive the pedals around.

The simplest freewheel device consists of two saw-toothed, spring-loaded

discs pressing against each other with the toothed sides together, somewhat

like a ratchet. Rotating in one direction, the saw teeth of the drive disc lock

with the teeth of the driven disc, making it rotate at the same speed. If the

drive disc slows down or stops rotating, the teeth of the driven disc slip

over the drive disc teeth and continue rotating, producing a characteristic

clicking sound proportionate to the speed difference of the driven gear

relative to that of the (slower) driving gear.

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ADVANTAGES AND DISADVANTAGES

By its nature, a freewheel mechanism acts as an automatic clutch, making

it possible to change gears in a manual gearbox, either up- or downshifting,

without depressing the clutch pedal

A freewheel also produces slightly better fuel economy on carburetted

engines and less wear on the manual clutch, but leads to more wear on the

brakes as there is no longer any ability to perform engine braking. This may

make freewheel transmissions dangerous for use on trucks and automobiles

driven in mountainous regions, as prolonged and continuous application of

brakes to limit vehicle speed soon leads to brake-system overheating

followed shortly by total failure.

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DESIGN METHODOLOGY

The freewheel was conceptualized with the following requirements in

mind:

Lightweight and compact

Ruggedness

Serviceability

Ease of fabrication in local small scale industries

Ease of driving in off road conditions

Design Process:

The primary aim of our freewheel is to help the vehicle in cornering by

making the outer wheel completely free from the main drive so that it can

rotate with the speed required for the vehicle to turn through that specific

radius. This will be very light in weight as compared to an open differential

in the same vehicle which is meant to do the same job. Plus we achieve the

cornering with the help of two freewheels at the shaft of each driving wheel

with very less weight than an open differential. The freewheel will be

specifically designed for an off road mini baja vehicle which runs on a

10HP Briggs & Stratton engine and has a CVT coupled with it. The final

reduction is taken through two chain drives where a reduction of 1:9 is

achieved.

Calculations of Torque:

An Automobile is accelerated by torque reacted by friction on its driven wheels. The torque is transmitted to the wheel by the transmission system. m= 300kg Cd=0.4 Rd=0.31m =45 degrees A=0.746m2 =0.16 (for earthen tracks) wd=30:60 =1.3 =0.85 or 85%

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Forces balanced on the vehicle

To calculate the tractive force to be supplied to the driven wheels, the free body diagram of the vehicle is drawn in Figure above. Thus the force required to accelerate the vehicle is given by:

Fz = mg(sin) + 0.5CdAv^2 + ma - mg(cos) (gravity) (drag) (inertia) (friction)

Case I:

We have to calculate the minimum force required to get the vehicle moving: The Vehicle starts up from rest and covers an incline of 100m at 45 degrees. The required speed at the top is 30km/h in 20 seconds. v= 8.33m/s u=0m/s t=20s a=0.34722 m/s2 Fz = 2081.01525 + 12.056 + 162.5013 332.962 = 1922.6105 N

Force on rear wheels = Fz * wd = 1282.38N = Fr i = Fr* Rd = 385.996 N-m a = i / = 454.11 N-m

Hence, 454.11 N-m is the desired torque on the driven shaft on

which the freewheels will be mounted.

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Case II:

We have to calculate the minimum force reduction required to keep the vehicle cruising at 60km/h on a level surface: v=19.44m/s a=0 =0

Thus, Fz= 470.8-65.6155 = 405.26 N Fr=267.477N i=80.243 Nm

a= 90.606Nm

Hence, 90.606Nm torque is required to be delivered at final driven

shaft on which the freewheels are mounted when the engine is at

its highest rpm.

Therefore, the freewheel is to be designed such that it can

provide a maximum torque of 454.11N-m and a maximum speed

of 60km/h

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CONSTRUCTION AND LAYOUT

Various designs of differentials currently being used for different purposes

were studied and their drawbacks were studied. Hence we started on the

freewheel drive mechanism which can tackle the shortcomings of

commonly used differentials like Open Differential, Locked Differential,

Limited Slip Differential etc.

Various parameters affecting the drive of the vehicle by using freewheels

were analysed. Also various designs of freewheel that could match the

torque requirements of a small motorized 4 wheel vehicle were considered.

The following layout of the vehicle drivetrain using freewheel was

selected.

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LITERATURE REVIEW

PAPER 1:

Title: The Development of a differential for the improvement of

traction control Authors: S E Chocolek(Gleason Corporation ,Rochester,

New York ,USA)

Introduction:

The Torsen(Torque-sensing) differential provides for the selection of an

optimal compromise between the two primary functions of any differential,

namely, transmitting power from a single power source to two drive axles

(or shafts) and permitting independent rotation of the two driven axles (i.e.,

differentiation). This compromise enables an increase in the total amount

of torque which can be conveyed by the drive axles under all traction

conditions, without unduly restricting differentiation. Differentiation is

necessary to accommodate different rotational speeds between drive axles

due to vehicle turning situations and variations in tire rolling radii. These

objectives are accomplished by associating the function of differentiation

with a proportioning torque between drive axles. The significance of this

important characteristic will be apparent from the following discussion,

beginning with an explanation of torque transfers within a differential.

Function of the Differential:

Torque Transfer: One of the two above-mentioned primary differential

functions, the transmission of power from a single driveshaft to the two

driven axles is most closely associated with the objective of traction

management (see Figure 1). Power, of course, is the product of torque and

rotational speed. However, since it is possible to express vehicular traction

as a reaction force acting at a given drive wheel radius, traction

considerations related to the function of power transfer to the drive axles

may be expressed in terms of torque alone.

Actually, two types of torque transfers may be identified in differentials.

The first being the one primary function related to the transfer of torque

from a single power source (engine) to the two drive axles. The second type

is the transfer of torque between the drive axles. The two types of torque

transfer are interrelated, and it is an important characteristic of the Torsen

differential to control torque transfers between drive axles and thereby

enhance the capacity of the differential to transfer an increased amount of

torque to the drive axles collectively.

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Structure for achieving Torque Bias:

Use of Invex Gearing:

Invex gearing in a Torsen differential includes a gear train arrangement

comprised of two or more pairs of satellite gears (called 'element gears') in

mesh with central helical gears (called 'side gears'). The pairs of element

gears are interconnected with each other by means of spur tooth

engagement. This particular arrangement consists of six element gears and

two side gears. The number of element gear pairs used in a specific design

is a function of overall torque capacity and space requirements.

The modified crossed axis helical gear mesh, element gear to side gear, is

designed and processed to provide instantaneous elliptical contact for

reduced tooth stress and increased tooth overlap engagement. In addition,

gear tooth helix angle, pressure angle and tooth depth proportions are

selected to further minimize stress and wear without sacrifice to function.

Torque Biasing Mechanism:

As previously stated, the torque biasing characteristic of the Torsen

differential is achieved by interconnecting the drive axles with an Invex

gearing configuration which selectively controls the generation of

frictional torques within the differential. It is important to note that there

are no intrinsic forces or pre-loads within the differentials which affect

transfers of torque between drive axles. All of the forces which are

controlled to produce frictional resistance between drive axles are derived

from transfers of torque between a single drive source and the drive axles.

The characteristic of torque bias is achieved in a very simple way. It is well

known that frictional forces are determined by the product of the coefficient

of friction of a given surface and the normal force applied to that surface.

Frictional torque, of course, is merely the application of that normal force

at an effective frictional radius. All of the forces which are active within

the differential are derivable from the torque which is being conveyed by

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the differential and the friction coefficients of surfaces within the

differential. Therefore, all of the frictional forces which are generated

within the differential, and all of the resulting resistant torques which

oppose the transfer of torque between drive axles, are proportional to the

torque being conveyed by the differential.

Since the maximum difference in torque between drive axles which can be

supported by friction is proportional to the combined torque of the drive

axles, the maximum bias ratio remains constant with respect to changes in

the combined drive axle torques.

In addition to providing a geared interconnection between drive axles

which permits the usual opposite relative rotation between the drive axles,

the gearing also distributes forces which may be generated to resist

differentiation over a large number of different surfaces within the

differential. The surfaces over which the Invex gearing distributes forces

are designed with different coefficients of friction and the Invex gearing is

designed to distribute different loads between the surfaces. Collectively,

the surfaces and the gearing are designed to distribute wear evenly over the

surfaces and to control the overall amount of friction within the differential

needed to achieve a desired bias ratio.

Comparison with Open Differential: In open differentials, the bevel gear

arrangement does not support any substantial difference in torque output to

the drive axles, hence there is a characteristic lack of resistance to the

differentiating function of the differential gearing. Due to this, any attempt

to apply greater torque to the wheel having better traction will result in

massive spinning up of the wheel having lesser traction.

The Torsen differential addresses this issue by the use of Invex gearing,

to impart torque proportioning characteristics, and is able to support a fixed

maximum ratio of torques between drive axles.

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PAPER 2:

Title: United States Patent for Limited Slip Differential (US 3831462

A, Aug 27,1974)

Authors: Jerry F. Baremor (Eaton Corporation, Cleveland , Ohio,USA)

Introduction:

This invention relates to open and limited slip differentials and more

particularly to open and limited slip differentials having a clutch system for

locking the differential when a predetermined level of differential action is

reached. The present invention provides a differential having a friction disc

clutch which is smoothly engaged to lock up the differential. To provide

this smooth engagement the clutch is of the self energizing type and-has a

dynamic coefficient of friction which constantly increases to at least 0.09

as the clutch is operated to an engaged condition under the influence of

self-energizing forces. The clutch is of the disc pack type and includes a

plurality of discs operably associated with a camming means which

engages a side gear of the differential.

It is an object of the present invention to provide a limited slip differential

mechanism having a disc type clutch system which operates to lock a

driving and a driven member together in a smooth manner to thereby

eliminate severe shock and impact loadings on the differential and other

associated components.

Function:

This differential mechanism comprises a carrier member defining a cavity,

which encloses differential gearing for transmitting drive forces from

carrier to the driven members, by means of a pair of side gears adapted to

be connected with the driven members and pinion gears disposed in

meshing engagement with said side gears and connected with said carrier.

To this, a set of self-energizing clutches is operatively connected between

the carrier and one of the side gears and is operable from a disengaged

condition to an engaged condition to retard relative rotation between the

side gear and carrier.

An actuator initates operation of the clutch pack, in response to a

predetermined speed of relative rotation between side gear and carrier. This

actuator mechanism includes a cam member having portions cooperable

with the side gear to effect axial loading of clutch pack upon relative

rotation of cam member and side gear. The actuator mechanism also

includes means for initiating relative rotation between side gear and cam

member.

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The locking action of the clutches on each side is triggered only on

achieving a certain degree of relative motion between the side gear and the

carrier(i.e. difference in rotational speed between the two).

Hence, the above type of differential can be said to allow a limited degree

of slippage between the wheels, above which the wheels are locked to the

differential carrier, and rotate with equal velocity.

Comparison with other differentials:

Clutch-pack differentials offer a good balance of control and torquebiasing

action, but are plagued by several unique problems:

1) Sudden onset of locking action may cause unpredictable driver

reactions and vehicle instability

2) Wearing of clutch disks over time results in deterioration of smooth

locking function

PAPER 3:

Title: United States Patent for Viscous Differential (US 3831462 A,

Aug 27,1974)

Authors: Mark A. Willet, James P. McCarthy(GKN corporation,

Michigan, USA)

Introduction:

A limited slip viscous differential in which the housing therefore is

gearingly connected with the drive axle and rotates therewith. Each of two

output axles from the limited slip viscous differential is connected

internally to a viscous coupling for transferring torque from the drive axle

to at least one of the two output axles when at least one of the two output

axles is rotating an angular velocity different from that of the housing. A

structure is provided for releasably retaining each of the output axles within

the housing.

Function:

In viscous couplings, interleave plates within a viscous fluid are used to

selectively interconnect the drive wheels. The controls therefor may be

either manually selective or automatically selective. The viscous coupling

has an outer drum circumferentially surrounding a pair of left and right

drums, each respectively connected to the left and right rear axles. Annular

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plates connected to the outer drum are interleaved with annular-plates

connected to the left and right drums. A mechanical linkage to the

driveshaft is provided by gearing between a driving bevel gear and a crown

gear connected to the outer drum.

A high viscous fluid is introduced into the first and second annular

chambers through the filler caps and, respectively. A preferred fluid is

silicone fluid having a viscosity of between 100,000 and 300,000

centistokes at 25 Centigrade; chamber fill is preferred to be between 75%

and 90% full.

It is well-known that a shearing action caused by the different angular

speeds of the second set of annular plates causes the fluid to heat and

expand thereby causing a transfer of torque between the first and second

annular plates.

Slip between the rear wheels occurs when each of the axles turn at different

angular velocities than that of the housing and, further, when one of the

rear wheels is experiencing slippage. In such a circumstance, the axle of

the rear wheel which is experiencing good traction will tend not to rotate,

or rotate much slower than the axle of the rear wheel which is slipping.

Accordingly, the first set of annular plates associated with the axle of the

slipping rear wheel will tend to rotate more nearly at the angular velocity

of the second set of annular plates than will the first set of annular plates

associated with the axle of the rear wheel which is experiencing better

traction.

What this means is that more heating and expansion of fluid will occur in

the annular chamber having the first annular plates associated with the axle

of the rear wheel having better traction, resulting in a greater transfer of

torque to the more tractive rear wheel than the slipping rear wheel.

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PAPER 4:

Generalized Equations for Sprag One-Way Clutch Analysis and

Design

Technical Paper

1998-02-23

David R. Chesney, John M. Kremer

This paper offers a similar analysis of another member of the one-way

clutch family, namely Sprag one-way clutches. Sprag one-way clutches are

clutches that freewheel in one direction, but transmit torque due to the

geometry of the sprag, when the races are rotated in the opposite relative

direction. ...Specifically, the paper discusses the theory of operation,

equilibrium equations, system deflections, system stresses, and dynamic

behaviour of a sprag one-way clutch. The paper derives and explains the

fundamental equations in terms of dimensionless units, in order to enable

the use of either English or metric units. ...ABSTRACT In 1997, Chesney

and Kremer wrote a paper entitled Generalized Equations for Roller

OneWay Clutch Analysis and Design [1]. The paper explained both the

static and dynamic behaviour of roller One-Way Clutches (OWC), and

described the practical application of esoteric stress equations to the design

of roller OWCs.

PAPER 5:

Advanced Overrunning Clutch Technology

Technical Paper

1978-02-01

Jules G. Kish

This paper summarizes the results of a 3 year research program to advance

the state-of-the-art in helicopter free-wheel units (overrunning clutches) by

permitting operation at 20,000 rpm. By designing the free-wheel unit to

operate at engine input speed instead of at the speed of the 2nd reduction

where it is usually located, the torque, and hence size and weight of the

unit, will be reduced. ...By designing the free-wheel unit to operate at

engine input speed instead of at the speed of the 2nd reduction where it is

usually located, the torque, and hence size and weight of the unit, will be

reduced.

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PAPER 6:

Light Commercial Vehicle with Locking Differential

Technical Paper

2013-10-07

Giovanni Giordani, Celso Fratta

In the light commercial vehicles and other wheeled vehicles, an open

differential is a device that allows each driven wheel to rotate in different

speeds during a curve or in limited grip conditions. On the other hand, when

one of the wheels loses the grip the differential will direct all the torque

available to the wheel that is spinning making the vehicle get stuck. In

certain applications, such as electrical power line maintenance in rural

areas requires a larger capacity drive vehicles due to low friction terrain.

To comply with this application requirement was developed the locking

differential speed sensitive that pulls both wheels at the same time offering

full locking axle and increasing the traction capacity of the vehicle. The

system automatically unlocks the wheel with higher speed when the speed

is different between them as happened in a curve. For this project the

locking system was applied to a light truck, which is an innovation in the

light commercial vehicles Brazilian market.

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Inferences From The Research Papers Studied:

An open differential has a tendency of giving more drive to the

wheel with less traction. Hence if one of the driving wheel is stuck

on ice and the other on ground then all the drive from the engine

will go to the wheel with less traction (wheel on ice).

Limited Slip Differentials are used to tackle the above mentioned

problem and are of mainly three types. Torsen, Regenerative

SelfEnergizing clutch and viscous

The engaging and disengaging motion of the energizing clutch and

viscous coupling can be thought of engaging and disengaging with

a freewheel with ratcheting action.

Sprag One way clutch and Roller one way clutch are other types of

commonly used freewheels which use spring action for engaging

and disengaging.

In sprag clutches the expansion of the spring passing through all the

sprags is expanded when the inner race is engaged with the outer

race. On rotating in the other direction the spring in tension comes

back to its normal extension and the inner race goes free.

In Roller One Way clutches every roller ball is connected to a small

spring where unlike in sprag clutches where all the sprags were

connected with one long spring. This also works in the same

manner

A great deal of weight and size can be reduced by using a

freewheel as they are small, easy design and hence, increasing the

serviceability.

For light vehicles in rural areas locking differentials are used as to

increase the traction on each wheel. This can also be achieved with

further weight reduction using two one way clutches.

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CONCLUSION

1) A freewheel Differential will provide vehicles with advantages

offered by an Open Differential and a Locked Differential.

2) Suppose, one rear wheel is stuck in a hole of very high resistance

and the other wheel is free.

In case of open differential:

The stuck wheel will not be able to come out as torque will

be divided equally between the wheels which will be in

sufficient to pull the car out of the hole.

In case of a freewheel differential:

The wheel speed will always be less than the Engine Speed

and both wheels will move with the same speed. Thus the

differential will act like a Locked Differential and the car

will be able to pull itself out.

3) Also, the percentage decrease in weight would be around the order

of 50-60%.

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Research Gaps and Scope for Future Work

Out of the types of differentials the Open Differential is the most

common. The main reason for this is it cost effectiveness in normal

Passenger Car usage. It means that if the spider gears are pushing on both

drive gears and one of them offers lots of resistance (tire sitting on

pavement) and the other side offers no resistance (up in the air, or sitting

on a patch of ice), then it will find a balance where both sides are

receiving almost no torque at all. All the rotational energy is guided to the

side with the least resistance. In the end, that side spins very fast and the

pressure on each drive gear is the same. Almost no torque is needed to

spin one wheel, and since the open diff always sends the same amount of

torque to both output shafts, almost no torque is going to the other side as

well.

Thus, the first problem of an Open Differential: Inadequate Torque to

the wheel in need of more torque, due to torque balancing between the

wheels

Hence a differential has to be designed which can tackle this problem with

minimum weight.

25

WORK TO BE DONE IN FUTURE

Further changes in the design will be made after prototyping and analysing

the validity of the design. At every stage the design will be analysed

through FEA and further optimisation on the design will be done.

SolidWorks, ANSYS, MSC ADAMS etc. softwares will be used for this

purpose.

Currently few designs have been made on SolidWorks and are still in their

nascent stage as further optimisation and FEA is to be done.

These designs were further optimised and developed for better ratcheting.

Another problem that has to be tackled is the reverse movement of a vehicle

using freewheel. The disadvantage of freewheels is that reverse movement

is not possible since the wheel goes free as the relative velocity of the wheel

is greater than the driving dogs. Hence the drive will travel till the dogs but

will not reach the wheel as it will go free. This problem will also be tackled

in this project in future.

26

REFERENCES

1) The Development of a differential for the improvement of traction control, S E Chocolek(Gleason Corporation ,Rochester,

New York ,USA)

2) United States Patent for Limited Slip Differential (US 3831462 A, Aug 27,1974), Jerry F. Baremor (Eaton Corporation, Cleveland , Ohio,USA)

3) United States Patent for Viscous Differential (US 3831462 A, Aug 27,1974), Mark A. Willet, James P. McCarthy(GKN

corporation, Michigan, USA)

4) Advanced Overrunning Clutch Technology,

Technical

Paper,1978-02-01, Jules G. Kish

5) Generalized Equations for Sprag One-Way Clutch Analysis and Design , Technical Paper, 1998-02-23, David R. Chesney, John M.

Kremer

6) Light Commercial Vehicle with Locking Differential , Technical

Paper, 2013-10-07, Giovanni Giordani, Celso Fratta

7) Selectable One-Way Clutch in GM's RWD 6-Speed Automatic Transmissions, Technical Paper, 2009-04-20, Farzad Samie,

Chunhao Joseph Lee, Brice Pawley

8) Automotive Transmissions, Harald NaunheimerBernd

BertscheJoachim RyborzWolfgang Novak

9) Heinz Heisler, Advanced Vehicle Technology, Butterworth

Heinmann Publications, 2nd edition, 2002.

10) T.K. Garrett, The Motor Vehicle, Butterworth Heinmann

Publications, 13th Edition, 2001

11) Automotive Engineering Fundamentals Richard Stone and Jeffrey

K. Ball

12) www.sciencedirect.com

13) www.technicaljournalsonline.com

14) www.packratworkshop.com

15) forum.atomiczombie.com